Trolley-harp for electric railways.



No.8o8,1e3. FATF-.MED 1350.26, 1905. l

J. MILLER, JR.

TROLLEY HARP EUR ELECTRIC RAILWAYS.

APPLICATION FILED APR.10, 1905.

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n www@ rErrEn STATES PATENT EEroE.

J OHLT MILLER, JR., OF AMESBURY, MASSACHUSETTS, ASSIGNOR TO VILLIAM E. BIDDLE, OF AMESBURY, MASSACHUSETTS.

T-ROLLEY-HARP FOR ELECTRIC RAILWAYS.l

Specification of Letters Patent.

Patented Dec. 26, 1905.

Application filed April 10, 1905. Serial No. 254,639.

To @ZZ whom vit may concern:

Be it known that I, JOHN MILLER, Jr., a citizen of the United States, residing at Amesbury, in the county of Essex and State of Massachusetts, have invented an Improvement in Trolley-Harps for Electric Railways, of which the following description, in connection With the accompanying drawings, is a specification, like figures on lthe drawings representing like parts.

My invention relates to the overhead contact device for transmitting current from the trolley-wire to the motor of an electric streetcar, my object being to provide a construction which will resist the tipping tendency of the wheel, and thereby prevent the liability of wearing elongated holes in the harp and trolley, so prevalent heretofore.

The leading features of my invention reside in providing a harp having its opposite sides spread and specially shaped to embrace and overlap the elongated conical hubs and bearing of the contained wheel and receive a fixed shaft, binding all the parts together, and so arranged as to receive and transmit current to the best advantage with minimum wear.

The constructional details of my invention will be pointed out more at length in the course of the following description, reference being had to the accompanying drawings, forming part of this speciiication, in which I have shown' a preferred embodiment of my invention.

In the drawings, Figure 1 is a central vertical longitudinal section of the complete embodiment of my invention. Fig. 2 shows the same in side elevation,partly broken away and sectioned for clearness of illustration.

The mechanism which constitutes my invention may be mounted in any desired manner, being' herein shown as mounted on a conductor-pole 1, such as is ordinarily carried on the top of an electric car. The harp comprises a lower socket portion 2, having branching arms 3, hollowed out at 4 and oppositely apertured at 5 to receive a steel pin or shaft 6, retained immovably by Cotter-pins or other suitable means 7, inserted through vertical openings S, extending down through the enlarged or thickened bearings 9, against whose inner fiat surfaces bear the ends of the hubs 10 and bearing-sleeve 11 of the trolley-wheel 12.

One of my principal objects is to prevent the Wabbling or lateral tipping and strain,

by the swaying of the car and trolley, so that it frequently happens that the trolley wheel and harp are soon worn with vertically-elongated slots in their opposite sides, with the result that as the wheel revolves there is a constant pounding and surging or up-and-down movement vof the pole, harp, and wheel, causing the latter to jump the wire and' greatly accelerating the wearing out of the parts, besides spattering oil, giving unsatisfactory electrical contact, &c. Accordingly the main feature of my'invention resides in spreading the harp and providing it with a long rigid bearing of exceedingly hard metal, such as hardened steel, for cooperating with a similarlyelongated hub and engaging surface of the wheel. Ivhave found that this construction braces against the swaying motion such as is caused in going around curves, as above explained, and effectually prevents the peculiar wear and destruction above explained.

The wheel 12 has a usual groovedf' peripharound a curve, and also this constructionk provides a long bearing, said sleeve 11 engaging the stationary shaft 6 for the entire width of the harp, as clearly shown in Fig. 1.

I still further reduce the swaying tendency by making the construction as light as possible, the walls 14 being made thin for this purpose, leaving a cavity 15, which may be packed with grease for lubricating purposes, if desired'. The walls are straight viewed in section, as shown in Fig. l-t'. e., their outer and inner surfaces are true right cones or are generated by a straight line revolving with the axle and extending at an angle of approxi- IOO mately forty-five degrees thereto. I have demonstrated by a long and severe trial of this construction that by having the hub ends tied together by the relatively heavy sleeve 11 the walls 14C may be not only thin, but decidedly liaring or steeply conical, as shown, without liability of bulging or breaking.` The angle of these walls, substantially as shown, is at approximately forty-five degrees to the vertical plane of the wheel and axis of rotation approximately in direct line with the thrust brought upon the wheel and harp in going around curves. This thrust is also firmly withstood by the relatively large bearing-surface of the harp at 9, which is engaged endwise by the large end surfaces of the parts 10 and 11, and no yielding or spreading apart of the harp is possible under said thrust and strain, because the sides 3 of the harp are tied unyieldingly together by the pin 9.

The outer surfaces of the hubs 10 are made cylindrical, and a guide-iiange 16 is preferably provided, as shown, to receive opposite contact-springs 17, whose lower ends are removably held in thin vertical slots 18, extending transversely of the harp in the direction of the trolley-axis and formed in enlargements 19, cast in the opposite sides 3 of the trolley-harp. The springs 17 are bent at their upper ends to partially embrace the hub 10, thereby getting a long bearing, and are under constant tension tending to spring forward to theleft, Fig. 2, thereby securing perfeet electrical contact. By having the spring' arranged to bear horizontally on the hub, as shown, a heavy spring may be used without interfering in any way with the desired extreme Width of harp and wheel, as would be Y the case if the spring were set edgewise between the harp and wheel, as is now usually done, and the electrical contact is certain, steady, and entirely out of all possible iniiuence of the grease or oil, which inevitably escape more or less at the end of the bearingsurface and would therefore be hable to smear Y the contact-spring if placed vertically against smoother in conjunction with each other than the usual construction or any other metals that I have been able to lind.

From the foregoing description it will be seen that although I have provided a light construction of all the parts, yet it possesses great strength, as all the opposite apparently frail parts are unyieldingly tied together, and there is no possibility of wearing verticallyelongated slots in the harp or in the wheel, because of the special protruding hub and wide bearing and bracing construction.

In going around curves there is no liability of wabbling, because instead of having a harp and hub only as wide as the trolley-rim (or in some of the common constructions even narrower than said rim) my construction gives a strong lateral bracing effect. Bearing in mind that the usual heavy springs at the lower end of the trolley-pole (not shown) yproduce a strong vertical thrust on the harp and trolley with reference to the feed-wire 21 and that the engagement of the side of the groove 13 with said wire produces a strong horizontal thrust on the harp and wheel, it will readily be understood that the resultant of these two forces is along an intermediate diagonal line which practically coincides with the angle of the thin wall 14, which therefore acts as a strut or brace. This thrust is taken up against the inner bearing-surface of the adjacent arm 3, which is anchored or tied to the opposite arm by the shaft 6.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. ln a device of the kind described, a trolley-harp having widely-branching' arms, a stationary shaft fast in the upper ends of said arms, a trolley-wheel mounted on said stationary shaft and having a heavy grooved periphery, and light, conical imperforate walls extending out laterally in opposite directions beyond said periphery and terminating in opposite cylindrical hubs, a bearing-sleeve fast at its lopposite ends in said hubs and mounted on said shaft, said sleeve tying said light walls together, said shaft tying said arms together, said shaft and sleeve a'ording a wide bearingsurface, and said light walls and arms coperating in bracing against tipping.

2. In a device of the kind described, a trolley-har p having widely-separated arms, a thin vertical slot in the lower part of one of said arms, extending transversely of said arm in the direction of the trolley-axis, a leaf-spring standing in said slot and extending upwardly flatwise with relation to the trolley-axis and edgewise to the trolley-wheel, and a trolleywheel mounted in said arms, having a hub IOC provided with a cylindrical outer surface forty-ve degrees to the latter, and the latter being provided with a removable tubular bearing secured at its opposite ends to said Wide axial portion, said Wheel having a large internal cavity formed by said Walls and bearing, and a stationary shaft mounted in said arms for supporting Said trolley-Wheel.

In testimony whereof I have signed my name to this specification in the presence of tvvo subscribing Witnesses.

JOHN MILLER, JR.

Witnesses:

ROBT. Gr. PATTEN, H. C. DONNELLY. 

